The main goal of this project is to create an online system that gives researchers easy access to American Time Use Survey (ATUS) data and documentation. The ATUS is a new time diary survey funded by the Bureau of Labor Statistics and fielded by the Census Bureau. ATUS respondents are drawn from households participating in the Current Population Survey (CPS). The data access system will encompass not only the ATUS data but also information from all of the monthly CPS interviews and CPS supplement interviews in which the ATUS households participated. At project completion, the data access system will cover all ATUS data collected during the seven-year period from 2003 through 2009. The ATUS data have enormous potential for research on topics including work and family, human capital formation, analyses of changes in social policy, and measurement of national output, among many others. Although there is evidence of considerable research interest in these new data, considerable programming effort is required to prepare data files that are suitable even for simple analyses of the ATUS. It would be enormously inefficient for every researcher who works with the data to duplicate this effort. Moreover, unless access to the ATUS can be enhanced and streamlined, the complexity of the data will discourage researchers from using them. The online data access system we propose will allow researchers to define study populations for data extracts;to create measures of time in user-defined activity aggregations, differentiated as desired by time of the day, week or year, by location and by the presence of specified others;and to combine ATUS data with CPS data pertaining to the ATUS household. The system will provide researchers with comprehensive and understandable documentation, including browsing functions and ready access to question texts, universe definitions and variable descriptions. User support will be provided through an online e-mail help line, a data users'forum, and two user conferences to be hosted during the project timeline.